Evaluación del equilibrio de adsorción de la dureza del agua sobre arcilla de Santa Teresa

In the Andean region of Ecuador, one of the problems in the presence of high concentrations of Calcium and Magnesium ions (Water Hardness) in natural waters; on average, the levels exceed 300 ppm, which generates problems for use on a domestic scale. Industrial and agricultural. This study animed to examine the adsorption process of calcium and magnesium ions dissolved in water using oxidic lithological material from the Santa Teresa area of the Guamote canton, province of Chimborazo, Ecuador. Adsorption beds were prepared from two particle size fractions, <75 µm and 75 – 150 µm, by extrusion, wich were cut between 2 and 3 mm long and were synthesized at 800 ºC for four hours. The adsorption tests were carried out in fixed bed batch systems with a flow rate of 0.9 mL/s, using natural and chemically activated substrates with diluted solutions at different pH, prepared from HCl and NaOH; in addition, the study of adsorption equilibrium by evaluating various mathematical models of isotherms and adsorption kinetics. The results showed that, by increasing the content of the adsorption bed in the system, the retention efficiency of water hardness increases, reaching a performance of 26.8% when using 1200 g of natural substrate. The activation pH, influences the adsorption efficiency; when using activated beds at an acidic ph of 2.3, the performance decreases to 16.5%; on the contrary, tests carried out with activated beds at a basic pH allow increasing the retention of the water hardness, obtaining 42.5% adsorption when using a pH of 11.5. Jointly, the adsorption isotherms were evaluated, which were adjusted to the Lagmuir model at acidic pHs (2.3; 4.3) and to the Dubinin-Radushkevich isotherm for alkaline pHs (11.5; 9.30)., showing that the correlation coefficient (R2) was more significant tan 0.90 in all cases. At the same times, the adsorption kinetics adjusted to the Pseudo Second Order model in all tests carried out at different pH. The results showed that the bed could regenerate after use, maintaining its efficiency, which suggests that the material and technique used could be an excellent option for the treatment of water with the presence of hardness.

• Autor principal: Campaña Arroyo, Jessica Maribel (author)
• Altres autors: Torres Llerena, Evelyn Jazmín (author)
• Format: bachelorThesis
• Idioma: spa
• Publicat: 2024
• Matèries: Adsorción; Arcilla; Dureza; Isoterma
• Accés en línia: http://dspace.unach.edu.ec/handle/51000/12826